Rema Kalenga Reserved Forest located in Chunarughat Upazila of Habiganj District of Sylhet Division is known as the second largest natural forest area in Bangladesh. In 1982, this forest area of about 1795 hectares was recognized as Rema Kalenga Wildlife Sanctuary. Rema-Kalenga Sanctuary covers the vast areas of Rema, Kalenga and Chanbari, which are included in the Kalenga Range of the Forest Department. Rema-Kalenga Sanctuary is home to about 638 species of trees, about 62 species of mammals, amphibians and reptiles and about 167 species of birds.
Among the various animals are the rare species of Malayan big squirrel, kulu, rhesus and shy monkey, Maya deer, Mukhpora Hanuman, owl, spectacled Hanuman, Mechobag, Gandagokul, wild boar, porcupine, beji and various species of snakes. Apart from this, among the different species of birds are Hill Myna, Mathura, Bhimraj, Red-headed Coot, Tia, Sepahi Bulbul, Chil, Basantabauri, Vulture, Wild Rooster, Wild Boar, Owl, Eagle and Fish Ranga.
The Rema-Kalenga Sanctuary has three photo-beautiful trails of 30 minutes, 1 hour and 3 hours. There is a tall observation tower to enjoy the beauty of the forest at a glance. And the observation tower is surrounded by a beautiful lake. There are tribal settlements of Tripura, Santal, Telugu and Urang communities. Besides, there is a tomb of the brave freedom fighter Shaheed Naik Abdul Mannan Biruttam near the BGB camp in the forest. On September 24, 1971, this brave warrior was martyred at this place. Bullet marks can still be seen on the teak tree next to the tomb.